title: The role of two SARP family transcriptional regulators in regulation of the auricin gene cluster in Streptomyces aureofaciens CCM 3239.
abstract: Two regulators, Aur1P and Aur1R, have been previously found to control expression of the aur1 polyketide gene cluster involved in biosynthesis of the angucycline-like antibiotic auricin in Streptomyces aureofaciens CCM 3239 in a cascade mechanism. Here, we describe the characterization of two additional regulatory genes, aur1PR2 and aur1PR3, encoding homologues of the SARP family of transcriptional activators that were identified in the upstream part of the aur1 cluster. Expression of both genes is directed by a single promoter, aur1PR2p and aur1Pr3p, respectively, induced in late exponential phase. Disruption of aur1PR2 in S. aureofaciens CCM 3239 had no effect on auricin production. However, the disruption of aur1PR3 dramatically reduced auricin compared with its parental wild-type strain. Transcription from the aur1Ap promoter, directing expression of the first biosynthetic gene in the auricin gene cluster, was similarly decreased in the S. aureofaciens CCM 3239 aur1PR3 mutant. Transcription from the aur1PR3p promoter increased in the S. aureofaciens CCM 3239 aur1R mutant strain, and the TetR family negative regulator Aur1R was shown to specifically bind the aur1PR3p promoter. These results indicate a complex regulation of the auricin cluster by the additional SARP family transcriptional activator Aur1PR3.
authors.affiliation: Institute of Molecular Biology, Slovak Academy of Sciences, 845 51 Bratislava, Slovak Republic.
authors.forename: Renata
authors.initials: R
authors.lastname: Novakova
authors.affiliation: Institute of Molecular Biology, Slovak Academy of Sciences, 845 51 Bratislava, Slovak Republic.
authors.forename: Alena
authors.initials: A
authors.lastname: Rehakova
authors.affiliation: Institute of Molecular Biology, Slovak Academy of Sciences, 845 51 Bratislava, Slovak Republic.
authors.forename: Peter
authors.initials: P
authors.lastname: Kutas
authors.affiliation: Institute of Molecular Biology, Slovak Academy of Sciences, 845 51 Bratislava, Slovak Republic.
authors.forename: Lubomira
authors.initials: L
authors.lastname: Feckova
authors.affiliation: Institute of Molecular Biology, Slovak Academy of Sciences, 845 51 Bratislava, Slovak Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Kormanec
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D015964:Gene Expression Regulation, Bacterial; D018942:Macrolides / Q000378:metabolism*; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics* / Q000502:physiology; D009154:Mutation; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D013304:Streptomyces aureofaciens / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D018942:Macrolides; D012097:Repressor Proteins; D015534:Trans-Activators; C505282:auricin